Difference in Working Principle
The raw materials of the flat die pellet mill drops down by the its own weight into the pelletizing room where they are compressed between the rollers and die to form pellets by going through the die holes. The raw materials of the ring die pellet mills is being transmitted from feed inlet to the material container under the centrifugal force, then is being swung to inside walls of roller of ring die pellet mill to form a circular layer, which is being driven to the contact surface of die and roller and compressed into our required models by reciprocal compression force of roller and die.

Difference in Feeding Style
The raw materials of the flat die pellet mills enters into the pelleting room by its own weight directly and evenly distributed. While the raw materials of ring die pellet mills is forced into the pelleting chamber and distributed by the high speed rotary scrapers.Difference in Pressure
Under the same diameter of mould, roller of ring die pellet mill is restricted by the diameter of die, so the pressure is restricted. While The pressure of flat die pellet mills is adjustable. Diameter of flat die is not restricted by the diameter of die and it could enlarge the space of inner bearing space.Adopting a big bearing not only strengthen bearing force of a roller, but also prolong service time. Difference in Discharging
Ring die pellet mill is rotating with high speed, so the percentage of damage is high. While flat ring die belongs to low speed rotate with low broken ratio.

Difference in Pellets formation
The flat die type form pellets by forcing the material through the holes. The ring die pellet mills form pellets by pressing the material to the inner perimeter of the roller.Difference in Pattern of Adjustment of Roller
Ring die pellet mill adjust the pressure through two screws on the eccentric gear which located at the center of roller. Flat die pellet mill adopts adjustment way of rotating manual operation and automatic hydraulic pressure. Which To Choose
Flat die pellet mill is suitable for small scale family workshop due to its low energy consumption and greater mobility. While ring die pellet mill has a large production, however with a high power consumption. Ring die pellet mill also has the feature of producing a nice pellet forming shape and high density (1-1.3%).
Though the comparison of the two different pellet mills, we can know the difference between them and their features. When purchasing the pellet mills, you must consider all the factors that will limit your production carefully and find the suitable pellet mill.